/* Copyright (c) 2001-2011 Timothy B. Terriberry
   Copyright (c) 2008-2009 Xiph.Org Foundation */
   /*
	  Redistribution and use in source and binary forms, with or without
	  modification, are permitted provided that the following conditions
	  are met:

	  - Redistributions of source code must retain the above copyright
	  notice, this list of conditions and the following disclaimer.

	  - Redistributions in binary form must reproduce the above copyright
	  notice, this list of conditions and the following disclaimer in the
	  documentation and/or other materials provided with the distribution.

	  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
	  OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
	  EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
	  PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
	  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
	  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
	  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
	  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */

#if defined(HAVE_CONFIG_H)
# include "config.h"
#endif
#include "os_support.h"
#include "arch.h"
#include "entenc.h"
#include "mfrngcod.h"

//#include "NailTester.h"

   /*A range encoder.
	 See entdec.c and the references for implementation details \cite{Mar79,MNW98}.

	 @INPROCEEDINGS{Mar79,
	  author="Martin, G.N.N.",
	  title="Range encoding: an algorithm for removing redundancy from a digitised
	   message",
	  booktitle="Video \& Data Recording Conference",
	  year=1979,
	  address="Southampton",
	  month=Jul
	 }
	 @ARTICLE{MNW98,
	  author="Alistair Moffat and Radford Neal and Ian H. Witten",
	  title="Arithmetic Coding Revisited",
	  journal="{ACM} Transactions on Information Systems",
	  year=1998,
	  volume=16,
	  number=3,
	  pages="256--294",
	  month=Jul,
	  URL="http://www.stanford.edu/class/ee398/handouts/papers/Moffat98ArithmCoding.pdf"
	 }*/

static int ec_write_byte(ec_enc *_this, unsigned _value) {
	if (_this->EC_DIFF) fprintf(stdout, "1a 0x%x\n", (unsigned int)_value);
	if (_this->EC_DIFF) fprintf(stdout, "8a 0x%x\n", (unsigned int)_this->nbits_total);
	if (_this->offs + _this->end_offs >= _this->storage)return -1;
	_this->buf[_this->offs++] = (unsigned char)_value;
	return 0;
}

static int ec_write_byte_at_end(ec_enc *_this, unsigned _value) {
	if (_this->EC_DIFF) fprintf(stdout, "1b 0x%x\n", (unsigned int)_value);
	if (_this->EC_DIFF) fprintf(stdout, "8b 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_write_byte_at_end");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputUintDeclaration("_value", _value);*/

	if (_this->offs + _this->end_offs >= _this->storage)
	{
		/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
		NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
		if (_this->EC_DIFF) fprintf(stdout, "int returnVal = EntropyCoder.ec_write_byte_at_end(through_ec_ctx, _value);\n");
		if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
		if (_this->EC_DIFF) fprintf(stdout, "Assert.AreEqual(-1, returnVal);\n");
		NailTestPrintTestFooter();*/
		return -1;
	}

	_this->buf[_this->storage - ++(_this->end_offs)] = (unsigned char)_value;

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "int returnVal = EntropyCoder.ec_write_byte_at_end(through_ec_ctx, in__value);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Assert.AreEqual(0, returnVal);\n");
	NailTestPrintTestFooter();*/

	return 0;
}

/*Outputs a symbol, with a carry bit.
  If there is a potential to propagate a carry over several symbols, they are
   buffered until it can be determined whether or not an actual carry will
   occur.
  If the counter for the buffered symbols overflows, then the stream becomes
   undecodable.
  This gives a theoretical limit of a few billion symbols in a single packet on
   32-bit systems.
  The alternative is to truncate the range in order to force a carry, but
   requires similar carry tracking in the decoder, needlessly slowing it down.*/
static void ec_enc_carry_out(ec_enc *_this, int _c) {
	if (_this->EC_DIFF) fprintf(stdout, "1e 0x%x\n", (unsigned int)_c);
	if (_this->EC_DIFF) fprintf(stdout, "8c 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_carry_out");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputIntDeclaration("_c", _c);*/

	if (_c != EC_SYM_MAX) {
		/*No further carry propagation possible, flush buffer.*/
		int carry;
		carry = _c >> EC_SYM_BITS;
		/*Don't output a byte on the first write.
		  This compare should be taken care of by branch-prediction thereafter.*/
		if (_this->rem >= 0)_this->error |= ec_write_byte(_this, _this->rem + carry);
		if (_this->ext > 0) {
			unsigned sym;
			sym = (EC_SYM_MAX + carry)&EC_SYM_MAX;
			do _this->error |= ec_write_byte(_this, sym);
			while (--(_this->ext) > 0);
		}
		_this->rem = _c&EC_SYM_MAX;
		if (_this->EC_DIFF) fprintf(stdout, "6a 0x%x\n", (unsigned int)_this->rem);
	}
	else _this->ext++;
	if (_this->EC_DIFF) fprintf(stdout, "6b 0x%x\n", (unsigned int)_this->ext);

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_carry_out(through_ec_ctx, in__c);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

static OPUS_INLINE void ec_enc_normalize(ec_enc *_this) {
	/*NailTestPrintTestHeader("ec_enc_normalize");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);*/
	/*If the range is too small, output some bits and rescale it.*/
	if (_this->EC_DIFF) fprintf(stdout, "8d 0x%x\n", (unsigned int)_this->nbits_total);
	while (_this->rng <= EC_CODE_BOT) {
		if (_this->EC_DIFF) fprintf(stdout, "8e 0x%x\n", (unsigned int)_this->nbits_total);
		ec_enc_carry_out(_this, (int)(_this->val >> EC_CODE_SHIFT));
		/*Move the next-to-high-order symbol into the high-order position.*/
		_this->val = (_this->val << EC_SYM_BITS)&(EC_CODE_TOP - 1);
		if (_this->EC_DIFF) fprintf(stdout, "1i 0x%x\n", (unsigned int)_this->val);
		_this->rng <<= EC_SYM_BITS;
		if (_this->EC_DIFF) fprintf(stdout, "7a 0x%x\n", (unsigned int)_this->nbits_total);
		_this->nbits_total += EC_SYM_BITS;
		if (_this->EC_DIFF) fprintf(stdout, "1ia 0x%x\n", (unsigned int)_this->nbits_total);
		if (_this->EC_DIFF) fprintf(stdout, "6c 0x%x\n", (unsigned int)_this->rng);
	}
	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_normalize(through_ec_ctx);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_enc_init(ec_enc *_this, unsigned char *_buf, opus_uint32 _size) {
	_this->buf = _buf;
	_this->end_offs = 0;
	_this->end_window = 0;
	_this->nend_bits = 0;
	/*This is the offset from which ec_tell() will subtract partial bits.*/
	_this->nbits_total = EC_CODE_BITS + 1;
	_this->offs = 0;
	_this->rng = EC_CODE_TOP;
	_this->rem = -1;
	_this->val = 0;
	_this->ext = 0;
	_this->storage = _size;
	_this->error = 0;
	_this->EC_DIFF = 0;
}

void ec_encode(ec_enc *_this, unsigned _fl, unsigned _fh, unsigned _ft) {
	if (_this->EC_DIFF) fprintf(stdout, "1f 0x%x\n", (unsigned int)_fl);
	if (_this->EC_DIFF) fprintf(stdout, "1g 0x%x\n", (unsigned int)_fh);
	if (_this->EC_DIFF) fprintf(stdout, "1h 0x%x\n", (unsigned int)_ft);
	if (_this->EC_DIFF) fprintf(stdout, "8f 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_encode");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputUintDeclaration("_fl", _fl);
	NailTestPrintInputUintDeclaration("_fh", _fh);
	NailTestPrintInputUintDeclaration("_ft", _ft);*/

	opus_uint32 r;
	r = celt_udiv(_this->rng, _ft);
	if (_fl > 0) {
		_this->val += _this->rng - IMUL32(r, (_ft - _fl));
		_this->rng = IMUL32(r, (_fh - _fl));
	}
	else _this->rng -= IMUL32(r, (_ft - _fh));

	if (_this->EC_DIFF) fprintf(stdout, "6d 0x%x\n", (unsigned int)_this->val);
	if (_this->EC_DIFF) fprintf(stdout, "6e 0x%x\n", (unsigned int)_this->rng);
	ec_enc_normalize(_this);

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_encode(through_ec_ctx, in__fl, in__fh, in__ft);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_encode_bin(ec_enc *_this, unsigned _fl, unsigned _fh, unsigned _bits) {
	if (_this->EC_DIFF) fprintf(stdout, "1i 0x%x\n", (unsigned int)_fl);
	if (_this->EC_DIFF) fprintf(stdout, "1j 0x%x\n", (unsigned int)_fh);
	if (_this->EC_DIFF) fprintf(stdout, "1k 0x%x\n", (unsigned int)_bits);
	if (_this->EC_DIFF) fprintf(stdout, "8g 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_encode_bin");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputUintDeclaration("_fl", _fl);
	NailTestPrintInputUintDeclaration("_fh", _fh);
	NailTestPrintInputUintDeclaration("_bits", _bits);*/
	
	opus_uint32 r;
	r = _this->rng >> _bits;
	if (_fl > 0) {
		_this->val += _this->rng - IMUL32(r, ((1U << _bits) - _fl));
		_this->rng = IMUL32(r, (_fh - _fl));
	}
	else _this->rng -= IMUL32(r, ((1U << _bits) - _fh));
	if (_this->EC_DIFF) fprintf(stdout, "6g 0x%x\n", (unsigned int)_this->val);
	if (_this->EC_DIFF) fprintf(stdout, "6h 0x%x\n", (unsigned int)_this->rng);
	ec_enc_normalize(_this);

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_encode_bin(through_ec_ctx, in__fl, in__fh, in__bits);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

/*The probability of having a "one" is 1/(1<<_logp).*/
void ec_enc_bit_logp(ec_enc *_this, int _val, unsigned _logp) {
	if (_this->EC_DIFF) fprintf(stdout, "1l 0x%x\n", (unsigned int)_val);
	if (_this->EC_DIFF) fprintf(stdout, "1m 0x%x\n", (unsigned int)_logp);
	if (_this->EC_DIFF) fprintf(stdout, "8h 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_bit_logp");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputIntDeclaration("_val", _val);
	NailTestPrintInputUintDeclaration("_logp", _logp);*/
	
	opus_uint32 r;
	opus_uint32 s;
	opus_uint32 l;
	r = _this->rng;
	l = _this->val;
	s = r >> _logp;
	r -= s;
	if (_val)_this->val = l + r;
	_this->rng = _val ? s : r;
	if (_this->EC_DIFF) fprintf(stdout, "6j 0x%x\n", (unsigned int)_this->val);
	if (_this->EC_DIFF) fprintf(stdout, "6k 0x%x\n", (unsigned int)_this->rng);
	ec_enc_normalize(_this);

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_bit_logp(through_ec_ctx, in__val, in__logp);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_enc_icdf(ec_enc *_this, int _s, const unsigned char *_icdf, unsigned _ftb) {
	if (_this->EC_DIFF) fprintf(stdout, "1n 0x%x\n", (unsigned int)_s);
	if (_this->EC_DIFF) fprintf(stdout, "1p 0x%x\n", (unsigned int)_ftb);
	if (_this->EC_DIFF) fprintf(stdout, "8i 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_icdf");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputIntDeclaration("_s", _s);
	NailTestPrintInputByteArrayDeclaration("_icdf", _icdf, 32);
	NailTestPrintInputUintDeclaration("_ftb", _ftb);*/

	opus_uint32 r;
	r = _this->rng >> _ftb;
	if (_s > 0) {
		_this->val += _this->rng - IMUL32(r, _icdf[_s - 1]);
		_this->rng = IMUL32(r, _icdf[_s - 1] - _icdf[_s]);
		if (_this->EC_DIFF) fprintf(stdout, "1oa 0x%x\n", (unsigned int)_icdf[_s - 1]);
		if (_this->EC_DIFF) fprintf(stdout, "1ob 0x%x\n", (unsigned int)_icdf[_s]);
	}
	else
	{
		_this->rng -= IMUL32(r, _icdf[_s]);
	}
	if (_this->EC_DIFF) fprintf(stdout, "6l 0x%x\n", (unsigned int)_this->val);
	if (_this->EC_DIFF) fprintf(stdout, "6m 0x%x\n", (unsigned int)_this->rng);
	ec_enc_normalize(_this);

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_icdf(through_ec_ctx, in__s, in__icdf, in__ftb);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_enc_uint(ec_enc *_this, opus_uint32 _fl, opus_uint32 _ft) {
	if (_this->EC_DIFF) fprintf(stdout, "1q 0x%x\n", (unsigned int)_fl);
	if (_this->EC_DIFF) fprintf(stdout, "1r 0x%x\n", (unsigned int)_ft);
	if (_this->EC_DIFF) fprintf(stdout, "8j 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_uint");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputUintDeclaration("_fl", _fl);
	NailTestPrintInputUintDeclaration("_ft", _ft);*/
	
	unsigned  ft;
	unsigned  fl;
	int       ftb;
	/*In order to optimize EC_ILOG(), it is undefined for the value 0.*/
	celt_assert(_ft > 1);
	_ft--;
	ftb = EC_ILOG(_ft);
	if (ftb > EC_UINT_BITS) {
		ftb -= EC_UINT_BITS;
		ft = (_ft >> ftb) + 1;
		fl = (unsigned)(_fl >> ftb);
		ec_encode(_this, fl, fl + 1, ft);
		ec_enc_bits(_this, _fl&(((opus_uint32)1 << ftb) - 1U), ftb);
	}
	else ec_encode(_this, _fl, _fl + 1, _ft + 1);

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_uint(through_ec_ctx, in__fl, in__ft);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_enc_bits(ec_enc *_this, opus_uint32 _fl, unsigned _bits) {
	if (_this->EC_DIFF) fprintf(stdout, "1s 0x%x\n", (unsigned int)_fl);
	if (_this->EC_DIFF) fprintf(stdout, "1t 0x%x\n", (unsigned int)_bits);
	if (_this->EC_DIFF) fprintf(stdout, "8k 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_bits");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputUintDeclaration("_fl", _fl);
	NailTestPrintInputUintDeclaration("_bits", _bits);*/

	ec_window window;
	int       used;
	window = _this->end_window;
	used = _this->nend_bits;
	celt_assert(_bits > 0);
	if (used + _bits > EC_WINDOW_SIZE) {
		do {
			_this->error |= ec_write_byte_at_end(_this, (unsigned)window&EC_SYM_MAX);
			window >>= EC_SYM_BITS;
			used -= EC_SYM_BITS;
		} while (used >= EC_SYM_BITS);
	}
	window |= (ec_window)_fl << used;
	used += _bits;
	_this->end_window = window;
	_this->nend_bits = used;
	if (_this->EC_DIFF) fprintf(stdout, "7c 0x%x\n", (unsigned int)_this->nbits_total);
	if (_this->EC_DIFF) fprintf(stdout, "7d 0x%x\n", (unsigned int)_bits);
	_this->nbits_total += _bits;
	if (_this->EC_DIFF) fprintf(stdout, "1ta 0x%x\n", (unsigned int)_this->nbits_total);
	if (_this->EC_DIFF) fprintf(stdout, "6n 0x%x\n", (unsigned int)_this->end_window);
	if (_this->EC_DIFF) fprintf(stdout, "6o 0x%x\n", (unsigned int)_this->nend_bits);

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_bits(through_ec_ctx, in__fl, in__bits);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_enc_patch_initial_bits(ec_enc *_this, unsigned _val, unsigned _nbits) {
	if (_this->EC_DIFF) fprintf(stdout, "1u 0x%x\n", (unsigned int)_val);
	if (_this->EC_DIFF) fprintf(stdout, "1v 0x%x\n", (unsigned int)_nbits);
	if (_this->EC_DIFF) fprintf(stdout, "8l 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_patch_initial_bits");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputUintDeclaration("_val", _val);
	NailTestPrintInputUintDeclaration("_nbits", _nbits);*/

	int      shift;
	unsigned mask;
	celt_assert(_nbits <= EC_SYM_BITS);
	shift = EC_SYM_BITS - _nbits;
	mask = ((1 << _nbits) - 1) << shift;
	if (_this->offs > 0) {
		/*The first byte has been finalized.*/
		_this->buf[0] = (unsigned char)((_this->buf[0] & ~mask) | _val << shift);
		if (_this->EC_DIFF) fprintf(stdout, "6p 0x%x\n", (unsigned int)_this->buf[0]);
	}
	else if (_this->rem >= 0) {
		/*The first byte is still awaiting carry propagation.*/
		_this->rem = (_this->rem&~mask) | _val << shift;
	}
	else if (_this->rng <= (EC_CODE_TOP >> _nbits)) {
		/*The renormalization loop has never been run.*/
		_this->val = (_this->val&~((opus_uint32)mask << EC_CODE_SHIFT)) |
			(opus_uint32)_val << (EC_CODE_SHIFT + shift);
	}
	/*The encoder hasn't even encoded _nbits of data yet.*/
	else _this->error = -1;

	if (_this->EC_DIFF) fprintf(stdout, "6q 0x%x\n", (unsigned int)_this->rem);
	if (_this->EC_DIFF) fprintf(stdout, "6r 0x%x\n", (unsigned int)_this->val);
	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_patch_initial_bits(through_ec_ctx, in__val, in__nbits);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_enc_shrink(ec_enc *_this, opus_uint32 _size) {
	if (_this->EC_DIFF) fprintf(stdout, "1w 0x%x\n", (unsigned int)_size);
	if (_this->EC_DIFF) fprintf(stdout, "8m 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_shrink");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);
	NailTestPrintInputUintDeclaration("_size", _size);*/

	celt_assert(_this->offs + _this->end_offs <= _size);
	OPUS_MOVE(_this->buf + _size - _this->end_offs,
		_this->buf + _this->storage - _this->end_offs, _this->end_offs);
	_this->storage = _size;

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_shrink(through_ec_ctx, in__size);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}

void ec_enc_done(ec_enc *_this) {
	ec_window   window;
	int         used;
	opus_uint32 msk;
	opus_uint32 end;
	int         l;
	if (_this->EC_DIFF) fprintf(stdout, "8n 0x%x\n", (unsigned int)_this->nbits_total);
	/*NailTestPrintTestHeader("ec_enc_done");
	if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("through_ec_ctx", _this);*/

	/*We output the minimum number of bits that ensures that the symbols encoded
	   thus far will be decoded correctly regardless of the bits that follow.*/
	l = EC_CODE_BITS - EC_ILOG(_this->rng);
	msk = (EC_CODE_TOP - 1) >> l;
	end = (_this->val + msk)&~msk;
	if ((end | msk) >= _this->val + _this->rng) {
		l++;
		msk >>= 1;
		end = (_this->val + msk)&~msk;
	}
	while (l > 0) {
		ec_enc_carry_out(_this, (int)(end >> EC_CODE_SHIFT));
		end = (end << EC_SYM_BITS)&(EC_CODE_TOP - 1);
		l -= EC_SYM_BITS;
	}
	/*If we have a buffered byte flush it into the output buffer.*/
	if (_this->rem >= 0 || _this->ext > 0)ec_enc_carry_out(_this, 0);
	/*If we have buffered extra bits, flush them as well.*/
	window = _this->end_window;
	used = _this->nend_bits;
	while (used >= EC_SYM_BITS) {
		_this->error |= ec_write_byte_at_end(_this, (unsigned)window&EC_SYM_MAX);
		window >>= EC_SYM_BITS;
		used -= EC_SYM_BITS;
	}
	/*Clear any excess space and add any remaining extra bits to the last byte.*/
	if (!_this->error) {
		OPUS_CLEAR(_this->buf + _this->offs,
			_this->storage - _this->offs - _this->end_offs);
		if (used > 0) {
			/*If there's no range coder data at all, give up.*/
			if (_this->end_offs >= _this->storage)_this->error = -1;
			else {
				l = -l;
				/*If we've busted, don't add too many extra bits to the last byte; it
				   would corrupt the range coder data, and that's more important.*/
				if (_this->offs + _this->end_offs >= _this->storage&&l < used) {
					window &= (1 << l) - 1;
					_this->error = -1;
				}
				_this->buf[_this->storage - _this->end_offs - 1] |= (unsigned char)window;
			}
		}
	}

	/*if (_this->EC_DIFF) fprintf(stdout, "ec_ctx ");
	NailTesterPrint_ec_ctx("expected_ec_ctx", _this);
	if (_this->EC_DIFF) fprintf(stdout, "EntropyCoder.ec_enc_done(through_ec_ctx);\n");
	if (_this->EC_DIFF) fprintf(stdout, "Helpers.AssertEcCtxEquals(expected_ec_ctx, through_ec_ctx);\n");
	NailTestPrintTestFooter();*/
}
